Method of arranging multilayer passive electronic components

ABSTRACT

Subject invention provides method of arranging multilayer passive electronic components, enabling simple arranging of rolled thin foil from a roll on a supporting block in order to form a stack, where supporting, plastic foil with thin foil ( 63 ) in it is led from unrolling mechanism ( 67 ) for unrolling the foil, over the cross knife ( 66 ) and over two rotating side knives ( 68 ), through the pressing tool ( 65 ), over the separating crossbar ( 610 ) and pulling mechanism ( 612 ) to the rolling mechanism ( 611 ) for rolling of the supporting foil, from which the thin foil is already separated, where the supporting block ( 57 ) is put under the pressing tool ( 65 ). The invention also provides the supporting block.

FIELD OF INVENTION

[0001] This invention belongs to the field of manufacturing electroniccomponents. More specifically it belongs to the field of arrangingmultilayer passive electronic components e.g. ceramic condensers,varistors, inductors, etc., composed or arranged from relatively thinlayers.

TECHNICAL PROBLEM AND STATE OF THE ART

[0002] Improvement of multilayer electronic component characteristicsnormally requires decreasing of layer thickness and increasing of numberof layers. Usually thin layer of ceramic or other material is broughtonto supporting substrate, normally a plastic foil. Separation of suchthin layer from the supporting foil and arranging into a stack ispractical problem, becoming even greater when thinner layers areapplied. Another problem is precise placement of each of electrodelayers against other electrode layers, especially when the number oflayers is large.

SHORT DESCRIPTION OF DRAWINGS

[0003] Subject invention is further described, with reference to thefollowing drawings, which show:

[0004]FIG. 1: an example of composing multilayer ceramic condenser

[0005]FIG. 2: procedure of arranging a stack

[0006]FIG. 3: shape of centering grooves of thinner supporting block

[0007]FIG. 4: shape of centering grooves of thicker supporting block

[0008]FIG. 5: method of centering of supporting block

[0009]FIG. 6: composing of rolled thin foil onto a supporting block in astack

[0010]FIG. 7: cutting edges of foil on supporting foil for composinginto a stack

[0011]FIG. 8: steps of composing a stack

[0012]FIG. 9: thin foil longitudinal cutting

[0013]FIG. 10: thin foil cross cutting

DESCRIPTION OF THE INVENTION

[0014] Subject invention provides solution to the problem of arrangingor composing of thin layers of multilayer electronic components andfurthermore it provides precise placement of each of electrode layersagainst other electrode layers, also when the number of electrode layersis large.

[0015]FIG. 2 shows typical course of composing a stack according to thepresent invention. Each foil is pressed on a supporting block, afterwhich a metallic layer is brought onto it, and the metallic layer isdried. These steps are then repeated, until the desired number of layersis reached.

[0016]FIG. 3 schematically shows a supporting block (a), which is ametallic plate of perpendicular shape. Dimensions of the supportingblock are equal to or larger from dimensions of the stack. Thesupporting block has two symmetrical wedge-shaped centering grooves (b),one on each of two opposite sides, where the top of each wedge-shapedgroove may be rounded up.

[0017] Said centering grooves (b) render possible positioning of thesupporting block with positioning or also called centering bolts, duringvarious operations are being carried out, like printing, foil arranging,product pressing, etc. The angle (c) of said centering wedge-shapedgrooves (b) is between 15° and 120°, which provides reliable adjustmentof centering bolts to a centering grooves (b). When the thickness (d) ofsupporting block (a) is smaller, centering grooves pass through thewhole thickness (d) of the supporting block (a). In case of largerthickness (d) of supporting block (a), the centering grooves (b) areformed only on the bottom side of the supporting block (a), as shown inFIG. 4. FIG. 5 shows method for centering of supporting blocks, whichare being deposited on a fastening plate (56), on each manufacturingstation, where positioning and fastening of supporting block is beingcarried out in a manner as described below.

[0018] Two positioning bolts (51, 52) are precisely guided in twoguiding elements (53, 54). The centering bolt (51) travels towards thesupporting block (57) until it sits into a corresponding centeringgroove. A limitation element (55), which is in this example a screw,limits traveling distance of the centering bolt (51). When movement ofthe positioning bolt (51) is concluded the positioning bolt (52) beginsto move towards the supporting block (57). When both positioning bolts(51, 52) sit in corresponding centering grooves the supporting block(51) is centered.

[0019] Supporting block (57) may be fastened onto a fastening plate (56)by means of suction, in which case at least one suction outlet (58) isprovided perpendicularly through the supporting plate (56), whichenables fastening of the supporting block (56) onto a fastening plate(57), by the means of vacuum. For fastening of larger supporting blocksonto a fastening plate (57), number of said outlets (58) is greater.

[0020]FIG. 6 shows method for simple arrangement of thin rolled foil ina stack on a supporting block. Supporting foil with thin foil (63) onit, is led from unrolling mechanism (67) for unrolling of supportingfoil, over the cross knife (66) and over two side knives (68), through apressing tool (65), over the separating crossbar (610) and pullingmechanism (612) to the rolling mechanism (611) for rolling of thesupporting foil. Supporting block (57) is put under the pressing tool(65) in such manner, that a notch (69) on a thin foil (63) is positionedas shown in FIG. 6.

[0021] As shown in FIG. 7, thin foil is cut with cross knife (66) andlongitudinally edged with rotating side knives (68).

[0022] According to above explanation of FIGS. 5 and 6, arrangement ofthin foil into a stack includes following steps, which are shown in FIG.8:

[0023] Step 1: Pressing of Thin Foil on a Supporting Block

[0024] Pressing toll presses thin foil, together with a supporting foilon a supporting block. Since the thin foil is relatively plastic andtherefore slightly adhesive, it will stick onto the supporting block. Ifthe foil lacks adhesiveness, thin layer of adhesive or wax will be puton the supporting block prior to the said pressing operation. Properpressing force is achieved with pneumatic, hydraulic or mechanicalpower. Pressing force and pressing time are adjustable, so for examplefoils with different mechanical and/or other properties may be used.

[0025] Step 2: Opening of the Pressing Tool

[0026] After prearranged pressing time, the pressing tool opens, withthe thin foil remaining stuck on a supporting block

[0027] Step 3: Separation of Thin Foil from the Supporting Foil

[0028] Crossbar (610), shown in FIG. 6, for separation of thin foil fromsupporting foil moves to the left side, thus separating supporting foilfrom the thin foil, which remains stuck on the supporting block.

[0029] Step 4: Pulling of the Supporting Foil for One Division

[0030] After the thin foil has been separated from the supporting foil,pulling mechanism (612) pulls the supporting foil for one divisiontowards the rolling mechanism. During the pulling operation rotatingside knives (68) longitudinally edge the thin foil. When the pullingoperation is completed, the cross knife (66) cuts the thin foil in crossdirection.

[0031] Implementation of side edging and cross cutting is furtherdescribed and shown below. The step of pressing (Step 1) may be repeateda number of times, while the thin foil is arranged one onto another, oron supporting blocks, which are after every new layer of thin foiltransported to a workstation, where a metallic layer is put on, driedand transported back in the pressing tool, as shown in FIG. 2.

[0032] Surface of a pressing tool is shaped in such a manner to provideequal pressure over the whole surface, and may be plane or on the otherhand it may follow irregular shape of the stack.

[0033]FIG. 9 schematically shows side edging of the thin foil. Purposeof this operation is:

[0034] side edging of the thin foil, to provide desired width

[0035] cutting off the edge of the thin foil, due to uneven thickness ofthe foil edge, as shown in FIG. 7.

[0036]FIG. 9 shows supporting plastic foil (91), carrying thin foil(92), which is rolled on a roller (99) and under a straining weight (98)and over rotating side knives (68) led to a pulling mechanism (112)shown in FIG. 6. Pulling mechanism (112) pulls both foils in directionof arrow (Y) shown in the FIG. 9. The edge of cutting rotating knife(68) with it's sharp edge touches the thin foil, and due to a forceprovided by a push bar (94), which is placed in a housing (97), sharpedge of the knife (68) cuts the thin foil (92).

[0037]FIG. 10 shows cross cutting of thin foil, which may also becarried out in a combination with longitudinal cutting (i.e. edging) ifso desired.

[0038] Cross cutting of the thin foil is implemented while between twomovements of the foil, thus when the foil is in a stand still position,and provides perpendicularity of the parts cut out from the thin foil,and furthermore perpendicular shape of the stack.

[0039] Supporting plastic foil (91) with thin foil (92) on the lowerside is stretched over the cross knife (66), which is with a knifehandle (104) fastened on the machine housing. Distance (x) between thethin foil (92) and the cross knife (66), enables undisturbed movement ofthe foil. When the foil is not moving, a cross-push bar (105) movesdownward, bends the foil and presses it against the cutting edge of across knife (66). The cross knife (66) cuts into and through the thinfoil (92), while the supporting foil (91) remains uncut.

[0040] As shown in FIG. 7, the length of the cross cut betweenlongitudinal cuts equals width of the cross cuts.

[0041] Purpose of above description of the subject invention is toillustrate the invention in the best way, and does not anyhow limit thescope of the invention. Skilled in the art will find differentvariations of the present invention. All such variations are within thescope and spirit of this invention. Scope of this invention is definedby the enclosed claims.

1. Method of arranging multilayer passive electronic components,enabling simple arranging of rolled thin foil from a roll on asupporting block in order to form a stack, where supporting, plasticfoil with thin foil (63) in it is led from unrolling mechanism (67) forunrolling the foil, over the cross knife (66) and over two rotating sideknives (68), through the pressing tool (65), over the separatingcrossbar (610) and pulling mechanism (612) to the rolling mechanism(611) for rolling of the supporting foil, from which the thin foil isalready separated, where the supporting block (57) is put under thepressing toll (65).
 2. Method of centering of supporting blocks, whichprovides precise arrangement of layers, characterized in that, that oneach working station said supporting block (57) is put on the fasteningplate (56), where the supporting block is positioned and fastened by themeans of two centering bolts (51, 52), each of them being guided incorresponding guiding element (53, 54), where the centering bolt (51)travels towards the supporting block (57) first, and sits into acorresponding centering groove (b), the movement of said centering bolt(51) being limited by a limitation element (55), and where after themovement of the centering bolt (51) is completed, the centering bolt(52) also travels toward the supporting block (57), so when bothcentering bolts (51, 52) sit in their corresponding centering grooves(b) the supporting block is centered and positioned, the supportingblock (57) may be fastened onto a fastening plate (56) by the means ofsuction, which is enabled by at least one suction vertical hole (58)passing through the fastening plate (56), which enables fastening of thesupporting block (57) onto a fastening plate (56), by the means ofvacuum.
 3. Method of centering of supporting blocks, which providesprecise arrangement of layers according to claim 2, characterized inthat, that when the supporting block (57) has larger dimensions, morethan one suction hole (58) passes vertically through the fastening plate(56), where the number of vertical suction holes (58) depends onsupporting block dimensions.
 4. Method of longitudinal cutting of thinfoil, characterized in that, that the supporting plastic foil (91) withthin foil (92) on it, is rolled on a roller (99) and under a strainingweight (98) and over rotating side knives (68) led to a pullingmechanism (112), to the pulling mechanism (112), which pulls both foilsin direction of arrow (Y), where the cutting rotating knife (68) withit's sharp edge touches the thin foil, and due to a force provided by apush bar (94), which is placed in a housing (97), sharp edge of theknife (68) cuts the thin foil (92) longitudinally.
 5. Method of thinfoil cross cutting, characterized in that, that supporting plastic foil(91) with thin foil (92) in it's lower side, is stretched over the crossknife (66), which is fastened on the machine housing, where the distance(x) between the thin foil (92) and the cross knife (66), enablesundisturbed movement of the foil, and where the said method isimplemented when the foil is not moving in such a manner that across-push bar (105) moves downward, bends the foil and presses itagainst the cutting edge of a cross knife (66), which cuts into andthrough the thin foil (92), while the supporting foil (91) remainsuncut.
 6. Supporting block (a), characterized in that, that it is in aform of metallic plate of perpendicular shape, with dimensions equal toor larger from dimensions of the stack, with two symmetricalwedge-shaped centering grooves (b) on of each of two opposite sides,where the top of each wedge-shaped groove (b) may be rounded up, and theangle (c) of said grooves (b) is between 15° and 1200, which providesreliable adjustment of centering bolt to a corresponding centeringgroove (b) and where said two grooves (b) enable centering of thesupporting block (a) with said two centering bolts.
 7. Supporting block(a) according to claim 6, characterized in that that when the thickness(d) of the supporting block (a) is smaller, centering grooves passthrough the whole thickness (d) of the supporting block (a), and whenthe thickness (d) of supporting block (a) is larger, the centeringgrooves (b) are formed only on the bottom side of the supporting block(a).